HIV and AIDS case rates give only a limited snapshot of the evolution of the HIV epidemic. Many people continue to present for diagnosis late in HIV disease and data from these persons gives a glimpse of risk behaviors that were occurring years ago. In addition, the most reliable data for estimating HIV incidence and HIV testing is collected through publicly-funded HIV counseling and testing sites. Though both of these data sets are extraordinarily helpful in characterizing the current epidemic, this data is limited. It is imperative that a mechanism be established and sustained that will enumerate behaviors known to facilitate HIV transmission and evaluate access to prevention services including HIV testing in a dynamic and real time manner. The National HIV Behavioral Surveillance project is just such a mechanism. It will provide a greater comprehension of HIV risk and HIV prevention behaviors, and will allow public health officials to respond in a timely manner to changes in the HIV epidemic with evolving prevention interventions and prevention messages. This project proposes to survey at least 500 persons who identify as men who have sex with other men, injection drug users, or heterosexuals at high risk for HIV in each of 25 sites across the country. The population at risk will rotate for each study cycle and the methods will utilize cutting edge surveillance technologies such as recruitment through respondent-driven sampling and the collection of data though handheld PDAs. Participants will be asked about HIV risk behaviors, about HIV prevention behaviors including HIV testing practices, and about knowledge of and access to HIV prevention services. In addition, all participants will be offered voluntary HIV testing allowing estimates of HIV prevalence to be made from a community perspective. Denver Public Health and the Colorado Department of Public Health and Environment participated in the first round of NHBS. We successfully met all of our objectives by developing formative assessments for the three respective communities: MSM, IDU, and heterosexual; by meeting and exceeding our recruitment goals for surveying; and by disseminating NHBS findings back out into the local community. This application will detail our research plan to again survey persons at risk for HIV, while building community and increasing collaborative efforts between the state and local health department, community based organizations, local researchers, and the communities themselves. By participating in the NHBS project for a second round, we will be able to make a significant contribution to our local and national understanding of HIV risk behaviors. We will be able to better evaluate HIV prevention services including testing. We will be able to develop community level estimates of HIV prevalence. Most importantly, through review and analysis of the data collected, we will be better poised to continue to respond to the ongoing HIV epidemic with needed effective prevention programs. [unreadable] [unreadable] [unreadable]